Aim 2 assesses the influence of the environment on the roots system. We will sample root tissue of rootstock cultivars '3309C', '1103P' and 'SO4' using the same vines from which the 'Marquette' scion samples will be collected in Aim 1. Our focus in the roots is on DNA methylation and on the expression of genes, miRNAs and siRNAs. A prerequisite of such studies is a genome sequence of each rootstock cultivar. Therefore, part of this aim is to generate a phased diploid genome sequence of '3309C', '1103P' and 'SO4'. As in Aim 1, phenotyping will be performed in all four replicated vineyards in South Dakota, New York, Pennsylvania and Missouri. As corresponding molecular data will also be generated in the scion of the same grafted vines, we will be able to comparatively analyze epigenetic and transcriptomic patterns in the rootstock and the scion. Phenotypic characterization of the roots will focus on their elemental composition (a phenotype also investigated in scion tissues), as nutrient uptake is one of the key functions of the root system which impacts vine health and fruit quality.
Aim 2 will allow us to answer the question of how diverse soil environments impact nutrient accumulation, epigenomic mechanisms and gene expression in a root genotype. Our unique experimental system enables us to determine if acclimation to the environment is accompanied by epigenomic changes that are convergent or different in the root and the shoot system and to what extent the elemental content of the scion reflects that of the rootstock. In addition, we will provide the scientific community with reference genome sequences of rootstock cultivars of economic importance.
Aim 2 will allow us to answer the question of how diverse soil environments impact nutrient accumulation, epigenomic mechanisms and gene expression in a root genotype. Our unique experimental system enables us to determine if acclimation to the environment is accompanied by epigenomic changes that are convergent or different in the root and the shoot system and to what extent the elemental content of the scion reflects that of the rootstock. In addition, we will provide the scientific community with reference genome sequences of rootstock cultivars of economic importance.